1. Field of the Invention
This invention relates generally to valve mechanisms, and more particularly to an improved valve mechanism which combines the functions of pressure regulating and fluid flow control. The combination pressure regulating and flow control valve of the present invention is adapted for many uses as, for example, for controlling the operation of an air cylinder in either one direction or both directions.
2. Description of the Prior Art
It is known in the valve art to provide pressure regulation to individual or multiple directional control valves with single or multiple pressure regulators to control the pressure supplied to the device being controlled. The use of multiple pressure regulators is expensive and awkward requiring special directional control valves and excessive piping. Where multiple directional valves are mounted in stacking fashion or on a common manifold base, it is extremely difficult and expensive to provide pressure regulation to individual outlets. It is not common to use such pressure regulators in the line between the outlet or cylinder port of the directional valve and the device being controlled because of cost, space and the relatively short life of diaphragms and other components of pressure regulators. It is common to provide flow control means in the line between the directional control valve and the device being controlled. Because of cost, complexity and space requirements, it has not been practicable in the past to provide both pressure regulator means and flow control means between the cylinder port of the directional control valve and the device being controlled. The result has been a waste of air requiring excessive pumping capacity, a waste of energy, and increase in the cost of using air as a power and control means.